The Research And Simulation Of Bandwidth Assignment Algorithm Based On The Multi-services Prediction Of EPON

With the fact that the Internet promptness popularizes,broadband business springs up in large amount,people increases by gradually to the bandwidth need,EPON (Ethemet Passive Optical Network) arises at the historic moment as the preferred plan resolving " the first one mile " problem then.EPON system has serious security issues for its particular P2M(Point to Multi-Point ) architecture.It is significant to study on and solve security issues of EPON for its mass commercial deployment.However,EFMA is not standard solution to bandwidth allocation in EPON.The common bandwidth allocations are either defective or not effective to the some problem. It is bound to its significance that how to improve the existing program and to develop the new measures.In this paper,the main study point is upstream dynamic bandwidth allocation technology of the EPON.It first introduces the development and trends of the access network,and compares several optical access networks.And then it presents the structure,working principle and the whole line frame structure of the EPON system based on the definition of EPON system,and analyses the technology characteristics as well as several key technologies of EPON.Based on the detailed analysis of characteristics of a variety of bandwidth allocation strategy in the upstream EPON access technology,a dynamic bandwidth allocation algorithm based on multi-service forecasting is put forward.The major work and results are as follows:(1) Analyze the system structure and working principle of EPON.For the structural characteristics of EPON,analyze a number of pstream communications in detail, focusing on the judgments for time synchronization and conflict of the TDMA technology.(2) A detailed analysis of the MPCP frame structure.In order to meet the needs of multi-service bandwidth better and reflect the real-time of multi-service,a new GATE and REPORT frame structure is designed based on the original design.At the same time, GATE / REPORT mechanism is analyzed in detail.According to the MPCP agreement, it analyzes the automatic discovery and registration process of ONU and its working principle.(3) Give a detailed analysis of IPACT algorithm,BGP algorithm and CBR algorithm,and their advantages and disadvantages.(4) For the real-time characteristics of multi-service EPON,an EPON bandwidth allocation algorithm based on multi-service forecast is stated,and its core idea and model and design are expounded.(5) Build the EPON module by OPNET simulation software,and give a simulation for the proposed algorithm,and Comparison of the high-priority business latency, bandwidth utilization and average packet delay.The experimental results shows that compared with the IPACT algorithm,MPDBA algorithm has good support for high-priority business.